8x³ - 8y³ = 8(x³ - y³) = 8(x - y)(x² + xy + y²)
2cos^2x-2sin2x+1=0.
2cos^2x - 4sinxcosx + 1 = 0
2cos^2x - 4sinxcosx + sin^2x + cos^2x = 0
sin^2x - 4sinxcosx + 3cos^2x = 0 /: cos^2x не рав. 0
tg^2x - 4tgx +3=0
(tgx - 1 )(tgx - 3 ) = 0
1) tgx = 1 ==> x = pi/4 +pik, k c Z
2) tgx = 3 ===> x = arctg(3) +pik, k c Z
Подробнее - на Znanija.com - znanija.com/task/3818797#readmore
<span>17+12√2 / 2√2+3 -2√2 = 0
17+6+3-2</span>√2=0
26-2√2=0 - не может такого быть
{3x-13>0 ; {3х>133 \ :3 ; {х>13\3
<span>{25-4x>0 ; {4х<25 \ :4 ; {х<6,25
6,25>х>13\3</span>